What is a concussion?

A concussion is a mild traumatic brain injury caused by a bump, jolt, or blow to the head. The sudden movement causes the brain to bounce around or twist inside the skull. This leads to stretching and damaging of brain cells and chemical changes in the brain. A jolt to the body can also cause a concussion if the impact is strong enough to cause the head to forcefully jerk backwards, forwards, or to the side.

A concussion is classified as "mild" because it is not usually life-threatening. However, the effects from a concussion can be serious and last for days, weeks, or even longer.